Handbook for Sound Engineers

1612 Chapter 46 environment. The 0 line represents the ambient (no sig- nal) state of the medium being modulated. This would be ...

Test and Measurement 1613 known and better developed than acoustical measure- ment methods. 46.3.2.3 The Transfer Function The e ...

1614 Chapter 46 time information can’t be observed on a magni- tude/phase plot. Any attempt to view both simultane- ously will o ...

Test and Measurement 1615 46.3.4.1 FFT Measurements The Fourier Transform is a mathematical filtering pro- cess that determines ...

1616 Chapter 46 The FFT of such a stimulus is a straight, horizontal line in the frequency domain. The time-honored hand clap te ...

Test and Measurement 1617 among contractors and consultants, who must often perform sound system calibrations in the real world ...

1618 Chapter 46 46.3.5.1 Dissecting the Impulse Response The audio practitioner is often faced with the dilemma of determining w ...

Test and Measurement 1619 (low frequencies) the direct field may include the effects of boundaries near the loudspeaker and micr ...

1620 Chapter 46 46.3.5.7 Estimate the Critical Distance DC Critical distance is easy to estimate. A quick method with adequate a ...

Test and Measurement 1621 decayed prior to reaching the right side of the screen. It should also be repeatable. Run the test sev ...

1622 Chapter 46 number of these time windows in succession, each sepa- rated by a time offset, can form a 3D plot known as a wat ...

Test and Measurement 1623 ment can be remedied by tapering the energy at the beginning and end of the window to zero using a mat ...

1624 Chapter 46 Select the microphone position. I usually begin by looking at the on-axis response of the loudspeaker as measur ...

Test and Measurement 1625 46.3.6 Human Perception Useful measurement systems can measure the impulse response of a loudspeaker/r ...

1626 Chapter 46 examines the ratio between early energy, late energy, and noise, the measurer must place cursors on the dis- pla ...

Test and Measurement 1627 orderly approach to achieving meaningful results that correlate with the perception of live listeners. ...

1628 Chapter 46 through a small loudspeaker (for testing microphones) or an XLR connector (for testing electronic devices) and a ...

Test and Measurement 1629 References D. Davis and C. Davis, Sound System Engineering, Focal Press, 1997, Boston, MA. The Heyser ...

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1631 Chapter 47 What’s the Ear For? How to Protect It by Les Blomberg and Noland Lewis 47.1 What’s the Ear For?................. ...